Oh no, I think it's happening

[Hatche90]

What brand def are you using and did you put in def additives in your def tank?

 

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[Hatche90]

Also, there’s a recalibration for the def system.

The issues you are having with your truck are common issues that a lot of other owners have had with their truck, this includes myself. When I first got my truck I had cels pop up for the o2 sensors, over time those cels stop popping up. This could be from the exhaust clamp and exhaust tape finally being seated and sealing the exhaust pipes. I then had a cel for low def fluid randomly pop up, I believe this might have been due to the def additive I add to the tank or maybe even a bad jug of def fluid. So, i disregarded the low def indication until i noticed that it started on permanently (this meaning that my def was truly low) and i filled it back up with fresh jugs of def. After this I haven’t had an issue with the def indicator saying I’m low on def when it’s truly at half a tank.

 

[Gill964]

I have had the same CEL (emissions related according to the app). First occurrence was around 15K. Dealer confirmed the engine was running fine and suggested hard acceleration where and when I could. It actually worked. The light went out but reappeared several other times, with the same fix. I never had any issues with DEF showing abnormally low.

Bumping up against the 36K warranty limit and I'm worried this will morph into something more serious. Were it not for this, I love the truck.

 

[Rdnkcaddy]

What brand def are you using and did you put in def additives in your def tank?

I use whatever is handy (truck stops when on the road). Last jug was from Tractor supply. I was told it should all be the same? Never used additives

 

[Rdnkcaddy]

Shop called and said it was a bad Position #2 Nox sensor

 

[Rick S]

Try this number. I've seen a lot of people contacting her and getting answers and results. I hope she can help you out.

 

[kobra357]

My father in law had that issue on his 2023 Duramax 3500 AT4 with 7500miles. Agreed it’s a common issue. Was fixed and has had zero problems since.

 

[Rdnkcaddy]

My father in law had that issue on his 2023 Duramax 3500 AT4 with 7500miles. Agreed it’s a common issue. Was fixed and has had zero problems since.

That’s comforting to hear! I was able to open a case with GM customer care to get some reimbursement on my rental and possibly hauling my truck back to me once fixed

 

[kobra357]

Ya he was able to get it fixed while at home and with the just check engine lights on. Good luck to you.